func checkOverlap(radius int, xCenter int, yCenter int, x1 int, y1 int, x2 int, y2 int) bool {
	f := func(i, j, k int) int {
		if i <= k && k <= j {
			return 0
		}
		if k < i {
			return i - k
		}
		return k - j
	}
	a := f(x1, x2, xCenter)
	b := f(y1, y2, yCenter)
	return a*a+b*b <= radius*radius
}